Continued efforts are needed in the U.S. to increase colorectal cancer (CRC) screening. For many people, their decision to screen will be influenced by information found on the internet. Such influential information can include receipt of tailored CRC feedback. However, a major concern is that receipt of online tailored CRC risk feedback that people interpret as being low risk can demotivate screening. Yet, as argued here, both higher and lower perceived risk can motivate screening when paired with appropriate persuasive messaging. To this end, pairing tailored CRC risk feedback with gain or loss framing - messages that highlight the benefits of screening (i.e., gain) or the costs of not screening (i.e, loss) - can be a potent combination to promote screening. As informed by Prospect Theory, matching of feedback of higher CRC risk with loss-framed messages as well as lower risk feedback with gain-frame messages should be more persuasive to motivate screening than the opposite pairings (i.e., mismatch). Yet no research has tested the matching between tailored CRC risk feedback and message framing to influence CRC screening. The primary goal of this study is to test the matching between level of comparative risk (i.e., how one's risk compares to others) and framing and mediators of effects in the context of individuals who obtain CRC risk and framing messages online (i.e., Internet). To simulate this online environment, using a firm the specializes in the conduct of web-based studies, we will obtain a sample of 760 individuals ages 50-75 who have never been screened for CRC. Individuals will review online information about CRC screening and receive tailored feedback as to their CRC risk factors and level of comparative risk. Participants within each stratum of comparative risk will then be randomized to receive messages either about the benefits of CRC screening (gain-frame) or the disadvantages of not screening (loss-frame). They will complete an immediate post-intervention survey assessing intentions to screen and hypothesized mediators and provide data six months later about screening behaviors. This study addresses the unresolved and neglected problem of what are the best tailored messages to give people at lower and higher CRC that can promote CRC screening. To this end, this study will be the first to explore in the online context the matching between tailored CRC risk feedback and message framing to influence CRC screening intentions, behaviors, and potential mediators of effects. This undertaking is important because it is yet unclear what best strategies to use to deliver tailored CRC risk feedback via the Internet to influence CRC screening.